Publications by authors named "Pfundt R"

Genetic diagnosis of rare diseases requires accurate identification and interpretation of genomic variants. Clinical and molecular scientists from 37 expert centers across Europe created the Solve-Rare Diseases Consortium (Solve-RD) resource, encompassing clinical, pedigree and genomic rare-disease data (94.5% exomes, 5.

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RICTOR is a key component of the mTORC2 signaling complex which is involved in the regulation of cell growth, proliferation and survival. RICTOR is highly expressed in neurons and is necessary for brain development. Here, we report eight unrelated patients presenting with intellectual disability and/or development delay and carrying variants in the RICTOR gene.

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Purpose: is one of the most frequently mutated genes in intellectual disability cohorts. Thus, far few adult-aged patients with -related disorder have been described, which limits our understanding of the disease's natural history and our ability to counsel patients and their families.

Methods: Data on patients aged 18+ years with -related disorder were collected through an online questionnaire completed by clinicians and parents.

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Article Synopsis
  • This study identifies a new type of autosomal recessive intellectual disability linked to genetic variants in the GTF3C3 gene, which is essential for proper RNA polymerase III activity.
  • Researchers employed various methods, including exome sequencing and Drosophila models, to analyze the effects of GTF3C3 variants found in twelve affected individuals from seven families.
  • The results showed that the variants lead to significant functional losses in the gene, correlating with symptoms like intellectual disability, motor issues, seizures, and brain structure abnormalities.
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The heterotrimeric protein phosphatase 2A (PP2A) complex catalyzes about half of Ser/Thr dephosphorylations in eukaryotic cells. A CAG repeat expansion in the neuron-specific protein PP2A regulatory subunit PPP2R2B gene causes spinocerebellar ataxia type 12 (SCA12). We established five monoallelic missense variants in PPP2R2B (four confirmed as de novo) as a cause of intellectual disability with developmental delay (R149P, T246K, N310K, E37K, I427T).

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Neurodevelopmental disorder with or without autism or seizures (NEDAUS) is a neurodevelopmental disorder characterized by global developmental delay, speech delay, seizures, autistic features, and/or behavior abnormalities. It is caused by CUL3 (Cullin-3 ubiquitin ligase) haploinsufficiency. We collected clinical and molecular data from 26 individuals carrying pathogenic variants and variants of uncertain significance (VUS) in the CUL3 gene, including 20 previously unreported cases.

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An increasing number of individuals with intellectual developmental disorder (IDD) and heterozygous variants in BCL11A are identified, yet our knowledge of manifestations and mutational spectrum is lacking. To address this, we performed detailed analysis of 42 individuals with BCL11A-related IDD (BCL11A-IDD, a.k.

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Pathogenic SOX11 variants have been associated with intellectual developmental disorder with microcephaly, and with or without ocular malformations or hypogonadotropic hypogonadism (HH) (IDDMOH, OMIM # 615866). In this article, we report seven new patients with de novo SOX11 variants. Five of the variants are missense, one nonsense, and one whole-gene deletion, most of them are novel variants.

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  • Researchers studied mutations in a gene that affects a key protein involved in cell signaling, which is linked to severe health issues like impaired immunity in patients.
  • The mutations were found to disrupt normal cell behavior by promoting excessive cell growth and responses to immune signals, specifically T cell receptor stimulation.
  • The mutant protein was shown to interfere with a regulatory protein, leading to heightened activity of important signaling pathways that contribute to cell growth and survival.
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  • KMT2C and KMT2D are important enzymes that modify genes, with KMT2C haploinsufficiency recently linked to Kleefstra syndrome 2, a neurodevelopmental disorder (NDD) with unknown clinical details.
  • A study involving 98 individuals found that most pathogenic variants in KMT2C span nearly all its exons, making variant interpretation difficult; the study also established a KMT2C DNA methylation signature for better classification of the disorder.
  • Key features of KMT2C-related NDD include developmental delays, intellectual disabilities, and distinct facial characteristics, setting it apart from similar conditions like Kleefstra and Kabuki syndromes, indicating the need for its renaming and
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The shift to a genotype-first approach in genetic diagnostics has revolutionized our understanding of neurodevelopmental disorders, expanding both their molecular and phenotypic spectra. Kleefstra syndrome (KLEFS1) is caused by EHMT1 haploinsufficiency and exhibits broad clinical manifestations. EHMT1 encodes euchromatic histone methyltransferase-1-a pivotal component of the epigenetic machinery.

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Uniparental disomy (UPD) is the inheritance of both homologues of a chromosome from only one parent. The detection of UPDs in sequencing data is not well established and a common gap in genetic diagnostics. We applied our in-house UPD detection pipeline to evaluate a cohort of 9212 samples, including multigene panels as well as exome sequencing data in a single, duo or trio constellation.

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  • The KINSSHIP syndrome, caused by de novo variants in the AFF3 gene, leads to intellectual disability, mesomelic dysplasia, and horseshoe kidneys, and is characterized by a dominant-negative effect from increased levels of AFF3.
  • Researchers screened intellectual disability cohorts and used animal models to explore additional inheritance patterns and found a range of variants in AFF3, including a de novo duplication linked to a severe phenotype and variants that caused milder symptoms.
  • Analysis of zebrafish models confirmed the pathogenic effects of specific AFF3 variations, showing that some mutations disrupted normal function while others led to more severe conditions in individuals with homozygous or compound heterozygous variants.
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Chung-Jansen syndrome is a neurodevelopmental disorder characterized by intellectual disability, behavioral problems, obesity and dysmorphic features. It is caused by pathogenic variants in the PHIP gene that encodes for the Pleckstrin homology domain-interacting protein, which is part of an epigenetic modifier protein complex. Therefore, we hypothesized that PHIP haploinsufficiency may impact genome-wide DNA methylation (DNAm).

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Utilizing trio whole-exome sequencing and a gene matching approach, we identified a cohort of 18 male individuals from 17 families with hemizygous variants in KCND1, including two de novo missense variants, three maternally inherited protein-truncating variants, and 12 maternally inherited missense variants. Affected subjects present with a neurodevelopmental disorder characterized by diverse neurological abnormalities, mostly delays in different developmental domains, but also distinct neuropsychiatric signs and epilepsy. Heterozygous carrier mothers are clinically unaffected.

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Deubiquitination is crucial for the proper functioning of numerous biological pathways, such as DNA repair, cell cycle progression, transcription, signal transduction and autophagy. Accordingly, pathogenic variants in deubiquitinating enzymes (DUBs) have been implicated in neurodevelopmental disorders and congenital abnormalities. ATXN7L3 is a component of the DUB module of the Spt-Ada-Gcn5 acetyltransferase (SAGA) complex and two other related DUB modules, and it serves as an obligate adaptor protein of three ubiquitin-specific proteases (USP22, USP27X or USP51).

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Article Synopsis
  • The study highlights the lack of understanding regarding comorbidities in individuals with neurodevelopmental disorders (NDDs), which are crucial for accurate diagnosis and prognosis.
  • PhenomAD-NDD is a newly developed database that compiles comorbid phenotypic data from over 51,000 individuals with NDD, utilizing a standardized classification known as Human Phenotype Ontology (HPO).
  • The findings reveal that congenital anomalies are significantly more common in the NDD population compared to the general population, and highlight that many important phenotypes related to genetic NDDs are not currently documented in existing clinical resources like OMIM.
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Mutations in proteasome β-subunits or their chaperone and regulatory proteins are associated with proteasome-associated autoinflammatory disorders (PRAAS). We studied six unrelated infants with three de novo heterozygous missense variants in PSMB10, encoding the proteasome β2i-subunit. Individuals presented with T-B-NK± severe combined immunodeficiency (SCID) and clinical features suggestive of Omenn syndrome, including diarrhea, alopecia, and desquamating erythematous rash.

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  • The DIP2 gene, first found in fruit flies, is crucial for neuron branching and regeneration, with vertebrate versions (DIP2A, DIP2B, and DIP2C) being highly conserved in the central nervous system.
  • Research showed that mutations in DIP2C are linked to developmental delays in expressive language and speech articulation in 23 affected individuals.
  • Alongside developmental issues, some individuals with DIP2C variants also presented with various cardiac defects and minor facial anomalies, highlighting a connection between the gene's loss-of-function and neurocognitive and physical phenotypes.
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THOC6 variants are the genetic basis of autosomal recessive THOC6 Intellectual Disability Syndrome (TIDS). THOC6 is critical for mammalian Transcription Export complex (TREX) tetramer formation, which is composed of four six-subunit THO monomers. The TREX tetramer facilitates mammalian RNA processing, in addition to the nuclear mRNA export functions of the TREX dimer conserved through yeast.

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Precise regulation of gene expression is important for correct neurodevelopment. 9q34.3 deletions affecting the EHMT1 gene result in a syndromic neurodevelopmental disorder named Kleefstra syndrome.

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Background: We previously described the KINSSHIP syndrome, an autosomal dominant disorder associated with intellectual disability (ID), mesomelic dysplasia and horseshoe kidney,caused by variants in the degron of AFF3. Mouse knock-ins and overexpression in zebrafish provided evidence for a dominant-negative (DN) mode-of-action, wherein an increased level of AFF3 resulted in pathological effects.

Methods: Evolutionary constraints suggest that other mode-of-inheritance could be at play.

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  • Rapid exome sequencing (rES) is becoming the go-to genetic test for critically ill patients, especially neonates and young infants, helping quickly identify genetic causes of rare diseases to guide treatment.
  • A study evaluated rES on 575 patients over four years, revealing a significant increase in referrals and a decrease in turnaround time for results, with an overall diagnostic yield of 30.4%.
  • Even when no genetic diagnosis was found, rES still influenced clinical decision-making, highlighting its value for patients of all ages and various rare conditions.
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Neurodevelopmental disorders with intellectual disability (ND/ID) are a heterogeneous group of diseases driving lifelong deficits in cognition and behavior with no definitive cure. X-linked intellectual disability disorder 105 (XLID105, #300984; OMIM) is a ND/ID driven by hemizygous variants in the gene encoding a protein deubiquitylase with a role in cell proliferation and neural development. Currently, only four genetically diagnosed individuals from two unrelated families have been described with limited clinical data.

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Cyclin D2 (CCND2) stabilization underpins a range of macrocephaly-associated disorders through mutation of CCND2 or activating mutations in upstream genes encoding PI3K-AKT pathway components. Here, we describe three individuals with overlapping macrocephaly-associated phenotypes who carry the same recurrent de novo c.179G>A (p.

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